I always had to sign extra consent forms for the Downs testing, if I wanted the blood draws for genetic disorders, etc. I've never heard of those being mandatory, even with the strictest of policies. One office did mandatory blood draws every visit, annoyed the crap out of me. The office I switched to, just had you pee in a cup. Beyond that, it was all optional (and I could've refused even that). I did the GD test, but it wasn't required.